In a combustion apparatus provided with: a combustion box having a connection flange part for connecting a heat exchanger to an upper end of the combustion box; a partition plate disposed inside the combustion box for partitioning space inside the combustion box into a combustion chamber and an air supply chamber which lies under the combustion chamber; and a plurality of laterally arrayed burners which are elongated longitudinally, the internal volume of the combustion box is increased without increasing a height dimension or without enlarging the connection flange part, thereby restraining the occurrence of resonance sounds. A drawn part projecting laterally outward of the combustion box is provided in such a portion of each side-plate part as is above the partition plate, over a predetermined range in the vertical and longitudinal directions. An upper side of the drawn part is preferably positioned below the upper end of the burners, and is preferably parallel with the upper end of the burners.

A gas burner (1) comprises a support plate (2) with a passage opening (8) for the gas and an annular wall (11) formed around the passage opening (8), a diffusing wall (19) and a further flow element (20,21,22) inserted on the annular wall (11) in flow communication with the passage opening (8), wherein the annular wall (11) forms a plurality of punches (16) with a recess (17) and an opposite projection (23), wherein the recess (17) accommodates a locking protuberance (25) of the diffusing wall (19) and the projection (23) extends in a locking hole (24) of the further flow element (20, 21, 22).

Burner Tubes for Gas Grills are disclosed. An example burner tube includes a linear burner tube including a venturi member disposed within a hollow interior of the linear burner tube proximate an open front end of the linear burner tube. The venturi member includes a front face having an opening configured to receive a neck of a gas valve, an upper flange extending rearwardly from an upper edge of the front face, the upper flange having a downwardly-extending V-shaped segment configured to constrict a region of the hollow interior, and a lower flange extending rearwardly from a lower edge of the front face, the lower flange having an upwardly-extending V-shaped segment configured to further constrict the region of the hollow interior.

The premixing device includes a first and a second venturis having a pressure reducing portion for air, and a gas supply passage for supplying fuel gas to the venturis, and generates air-fuel mixture by mixing fuel gas with air flowing in the venturis by using a fan and supplies the air-fuel mixture to a burner. A first and a second nozzles for reducing pressure of fuel gas are disposed in the gas supply passage, and the first and the second nozzles are formed in the same nozzle shape as the pressure reducing portion of the first and the second venturis.

A premixing device includes a first and a second venturi in which air flows by rotation of a centrifugal fan, first and second communication openings disposed in the venturis, respectively, for allowing fuel gas supplied from a gas supply passage to flow out, a flap valve capable of opening and closing the second venturi on a side downstream of the second communication opening, and an equalizing valve disposed in the gas supply passage on a side upstream of the first and the second communication openings. The gas supply passage, which connects between an outlet of the equalizing valve and the first and the second communication openings, diverges from the outlet of the equalizing valve to independently form a first gas passage and a first straight path, and a second gas passage and a second straight path for the venturis, respectively.

A combustion apparatus having: an upstream-side air supply chamber and a downstream-side mixing passage, both being respectively interposed between a fan and a burner; and a zero governor which is interposed in a gas supply passage and which adjusts a secondary gas pressure to a pressure equivalent to an internal pressure in the air supply chamber, thereby enabling to maximize a turndown ratio to the extent possible. The combustion apparatus has: first and second, totally two, mixing passages; a first gas outlet which is in communication with a narrowed part of the first mixing passage; a second gas outlet which is in communication with a narrowed part of the second mixing passage; a first air valve which varies an opening degree of an air inlet of the first mixing passage; a second air valve which varies an opening degree of an air inlet of the second mixing passage; and a gas valve.

Burner tubes for gas grills are disclosed. An example burner tube includes an open front end, a closed rear end located opposite the open front end, opposing upper and lower surfaces extending between the open front end and the closed rear end, opposing right and left side surfaces extending between the upper surface and the lower surface and between the open front end and the closed rear end, and a hollow interior defined by the upper surface, the lower surface, the right side surface, and the left side surface. The hollow interior has a rectangular cross-sectional profile that tapers in a direction moving from the open front end toward the closed rear end. The burner tube further includes a plurality of gas ports extending upwardly from the upper surface, with each one of the gas ports having an exit opening raised above the upper surface.

A burner includes a base and a combustion tray, wherein the base has an inlet pipe and two horn-shaped tubes. The horn-shaped tubes are connected to opposite sides of the inlet pipe, wherein each of the horn-shaped tubes respectively has a first section. A length of the first sections is no less than an inner diameter of the inlet pipe at where the horn-shaped tubes are connected to. The combustion tray is engaged with the base, and communicates with the horn-shaped tubes. Whereby, gas and air could be fully mixed while flowing through each of the first sections. The symmetrical horn-shaped tubes could direct the airflow to the combustion tray, where the airflow could be outputted from flame vents of the combustion tray, whereby to generate more even flame, and to enhance the heating efficiency.

A burner resonance canceling apparatus adapted to cancel a resonance caused in a burner tube having a side wall, apertures disposed on the side wall, a first end configured for receiving a fuel mixture flow, a closed second end, a central axis extending through the first end and the second end, the apparatus includes a member having an enlarged end, a reduced end and a central axis extending through the enlarged end and the reduced end, wherein the enlarged end is configured to be positioned at the second end, the central axes are substantially coaxially disposed and the reduced end is configured to face the fuel mixture flow brought through the first end into the burner tube and the burner tube and the member cooperate to define a chamber the fuel mixture flow is configured to traverse from the reduced end to the enlarged end.

A heat exchanger plate for a plate heat exchanger (12) includes a first side, a second side and a center point (P) through which an imaginary center axis (A) extends in a direction perpendicular to a plane of the plate. The plate comprises a first port for a first medium, and at least a second port and a third port for a second medium. The plate further comprises a first sealing arranged on the second side around the first port, a second sealing arranged on the second side at a circumference of the plate, and a closed third sealing arranged between the first and second sealings to form a first heat transfer area and a second heat transfer area separated from the first heat transfer area. The second port is arranged in the first heat transfer area and the third port is arranged in the second heat transfer area.